Launching a new national political party in the United States may be more difficult than sending a man to Mars.

Elon Musk, the world’s richest man, who last year was the nation’s biggest known political donor, now says that he is trying to do both. But while the effort to achieve interplanetary travel has made slow progress for over 20 years, the past several decades of American politics are littered with abandoned attempts to disrupt the two-party system.

It remains to be seen how serious Mr. Musk is about the new political project, and whether it will evolve from musings on his social-media platform to a fact of real life. While he declared on Saturday that “Today, the America Party is formed,” so far he has yet to register it with the Federal Election Commission.

As with many of his tweet-length proclamations, Mr. Musk’s plans for the new party are opaque. His private conversations about it so far have been conceptual and not focused on the details of what it would take to bring it to fruition, according to two people briefed on those talks. Some advisers to Mr. Musk who have also been involved in these early talks, however, appear more focused on those details and are soliciting more feedback from experts, according to one of the people.

Mr. Musk has said the America Party would be a new entity and would have the goal of disrupting the two major parties’ hold on the federal government.

Should he eventually tire of the idea, it would not be the first time he offered a grand pronouncement in an X post before either walking it back or letting it wither as he moved on to a new pursuit. Still, some notions that originated as seeming jokes by Mr. Musk — like his early purchase of shares in Twitter — have ended with world-altering investments.